Frost dates for Olympia Airport, WA
At Olympia Airport, the median last spring frost (32°F) is Apr 29 and the median first fall frost is Oct 14, for a typical growing season of 169 days. For a 90% chance that the last frost has passed, wait until May 15. Nearby ZIP codes are in USDA hardiness zones 8a to 8b.
- Apr 29Last spring frost (median)50% chance of 32°F after this date
- May 15Safer planting date10% chance of 32°F after this date
- Oct 14First fall frost (median)50% chance of 32°F by this date
- 169 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 30 | May 15 | May 31 |
| 32°F | Apr 11 | Apr 29 | May 15 |
| 28°F | Mar 12 | Apr 5 | Apr 29 |
| 24°F | Feb 7 | Mar 6 | Apr 1 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 12 | Sep 28 | Oct 14 |
| 32°F | Sep 28 | Oct 14 | Nov 1 |
| 28°F | Oct 9 | Nov 1 | Nov 24 |
| 24°F | Oct 28 | Nov 20 | Dec 21 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 113 days | 135 days | 158 days |
| 32°F | 144 days | 169 days | 195 days |
| 28°F | 181 days | 210 days | 239 days |
| 24°F | 225 days | 261 days | 303 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 98501 | 8a | 10 to 15°F | 2 km |
| 98503 | 8b | 15 to 20°F | 10 km |
| 98512 | 8a | 10 to 15°F | 11 km |
| 98505 | 8b | 15 to 20°F | 12 km |
| 98513 | 8b | 15 to 20°F | 13 km |
| 98502 | 8b | 15 to 20°F | 15 km |
| 98506 | 8b | 15 to 20°F | 15 km |
| 98516 | 8b | 15 to 20°F | 17 km |
| 98556 | 8a | 10 to 15°F | 21 km |
| 98576 | 8b | 15 to 20°F | 24 km |
| 98597 | 8b | 15 to 20°F | 34 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USW00024227, at 46.9733, -122.9033, elevation 57 m (188 ft).
- Data quality: Standard (24+ years of data), 30 years of freeze data.
- Average days per year at or below 32°F: 77.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Centralia (28 km)
- Shelton Sanderson Field (34 km)
- Elma (38 km)
- Tacoma Narrows Airport (41 km)
- Matlock 8 S (42 km)
- Tacoma #1 (48 km)
- Cushman Powerhouse #2 (48 km)
- McMillin Rsvr (52 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.